This invention relates to methods and reagents for detecting mispaired nucleotides in duplex nucleic acids for use, for example, in identifying genetic variations in nucleic acid sequences for research, therapeutic, and diagnostic applications.
Genetic variation occurs at approximately 1 out of every 100 bases within the genome. Research aimed at discovering genetic variation associated with diseases or disease therapies, as well as diagnostic tests aimed at using genetic information to manage patient care, requires efficient methods for detecting and typing genetic variance in various test sequences. Variances may be detected by a variety of methods. Many of these methods require the use of a probe with a unique sequence (representing a single allelic form of the sequence) as a reference by which to identify differences in the sequences of homologous DNA segments in patient test samples. Probes with a unique sequence are commonly produced from cloned DNA or cDNA. However, the use of probes from cloned DNA limits the ability to identify variances to DNA segments for which such clones are readily available, or alternatively requires the cloning of each DNA segment to be analyzed.